/*
 * $Id: ShapeUtils.java 4082 2011-11-15 18:39:43Z kschaefe $
 *
 * Copyright 2006 Sun Microsystems, Inc., 4150 Network Circle,
 * Santa Clara, California 95054, U.S.A. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
package org.jdesktop.swingx.util;

import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Polygon;
import java.awt.Shape;
import java.awt.font.GlyphVector;
import java.awt.geom.AffineTransform;
import java.awt.geom.Area;
import java.awt.geom.Ellipse2D;
import java.awt.geom.GeneralPath;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;

/**
 * 
 * @author joshy
 */
public final class ShapeUtils {

	/** Creates a new instance of ShapeUtils */
	private ShapeUtils() {
	}

	public static Shape generatePolygon(int sides, int outsideRadius, boolean normalize) {
		return generatePolygon(sides, outsideRadius, 0, normalize);
	}

	public static Shape generatePolygon(int sides, int outsideRadius, int insideRadius, boolean normalize) {
		Shape shape = generatePolygon(sides, outsideRadius, insideRadius);
		if (normalize) {
			Rectangle2D bounds = shape.getBounds2D();
			GeneralPath path = new GeneralPath(shape);
			shape = path.createTransformedShape(AffineTransform.getTranslateInstance(-bounds.getX(), -bounds.getY()));
		}
		return shape;
	}

	public static Shape generatePolygon(int sides, int outsideRadius, int insideRadius) {
		if (sides < 3) {
			return new Ellipse2D.Float(0, 0, 10, 10);
		}

		AffineTransform trans = new AffineTransform();
		Polygon poly = new Polygon();
		for (int i = 0; i < sides; i++) {
			trans.rotate(Math.PI * 2 / sides / 2);
			Point2D out = trans.transform(new Point2D.Float(0, outsideRadius), null);
			poly.addPoint((int) out.getX(), (int) out.getY());
			trans.rotate(Math.PI * 2 / sides / 2);
			if (insideRadius > 0) {
				Point2D in = trans.transform(new Point2D.Float(0, insideRadius), null);
				poly.addPoint((int) in.getX(), (int) in.getY());
			}
		}

		return poly;
	}

	public static Shape generateShapeFromText(Font font, char ch) {
		return generateShapeFromText(font, String.valueOf(ch));
	}

	public static Shape generateShapeFromText(Font font, String string) {
		BufferedImage img = GraphicsUtilities.createCompatibleTranslucentImage(1, 1);
		Graphics2D g2 = img.createGraphics();

		try {
			GlyphVector vect = font.createGlyphVector(g2.getFontRenderContext(), string);
			Shape shape = vect.getOutline(0f, (float) -vect.getVisualBounds().getY());

			return shape;
		} finally {
			g2.dispose();
		}
	}

	/**
	 * Sets the clip on a graphics object by merging a supplied clip with the
	 * existing one. The new clip will be an intersection of the old clip and
	 * the supplied clip. The old clip shape will be returned. This is useful
	 * for resetting the old clip after an operation is performed.
	 * 
	 * @param g
	 *            the graphics object to update
	 * @param clip
	 *            a new clipping region to add to the graphics clip.
	 * @return the current clipping region of the supplied graphics object. This
	 *         may return {@code null} if the current clip is {@code null}.
	 * @throws NullPointerException
	 *             if any parameter is {@code null}
	 */
	public static Shape mergeClip(Graphics g, Shape clip) {
		Shape oldClip = g.getClip();
		if (oldClip == null) {
			g.setClip(clip);
			return null;
		}
		Area area = new Area(oldClip);
		area.intersect(new Area(clip));// new Rectangle(0,0,width,height)));
		g.setClip(area);
		return oldClip;
	}
}
